Throw away tips for metal cutting tools

ABSTRACT

A throw away tip for a metal cutting tool comprising a right prism of hard material, each end face of the prism having at least two identical cutting corners and being formed with a plurality of tapering recesses of V-shaped section each recess having its narrowest end adjacent one of said cutting corners of the associated end face.

. I United States Patent 1 {111 3,751,782 Fruish Aug. 14, 1973 [54] THROW AWAY TIPS FOR METAL CU'I'I'ING 3,557,416 1/1971 Jones 29/95 TOOLS 2,677,170 5/1954 Kuns et a1...

3,137,918 6/1964 Breunin 29/96 [75] Inventor: Harvey Fruish, Northampton, 8

England Primary Examiner-Leonidas Vlachos [73] Assignee: Alfrled glerbert Limited, Coventry, Atwmey Ho]man & Stem I Eng an' [22] Fileda- May 12, 1971 [57] ABSTRACT 21 A L NQ; 142,455

A throw away tip for a metal cutting tool comprising a right prism of hard material, each end face of the prism c(3.1. 29lg5zg, having at least two identical cutting comers and being [58] Fneid 29295 96 formed with a plurality of tapering recesses of a c shaped section each recess having its narrowest end adjacent one of said cutting corners of the associated end [56] References Cited face UNITED STATES PATENTS 3,504,413 4/1970 Siewert et a1. 29/96 7 Claims, 4 Drawing Figures PATENTED Au: 1 4191s saw 1 .or 2

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INVENT 50am PATENImAuc 1 4191s 3,751,782

sum 2 or 2 INVENTOR THROW AWAY TIPS FOR METAL CUTTING TOOLS This invention relates to throw-away tips for metal cutting tools.

A throw-away tip in accordance with the invention comprises a right prism of hard material, each end face of the prism having at least two identical cutting corners and being formed with a plurality of tapering recesses of V-shaped section each recess having its narrowest end adjacent one of said cutting comers of the associated end face.

IN THE ACCOMPANYING DRAWINGS FIG. 1 is an elevation of one example of a tip in accordance with the invention,

FIG. 2 is an enlarged fragmentary section on line 2-2 in FIG. 1, and

FIGS. 3 and 4 are elevations of alternative forms of tip. 7

The tip shown is a square-section right prism and is formed of hard material such as tungsten carbide. Each end face of the prism is square and thus has four identical right-angle corners. In each end face there are formed four tapering recesses 10 of V-shaped crosssection. Each such recess 10 has its narrower end adjacent a corner of the face. One end of the recess 10 is defined by two flank surfaces ll, 12 inclined to one another at an angle in the range l to 1 and equally inclined to the end face. The lines l3, 14 where the flank surfaces ll, 12 intersect the end face are inclined to one another at an angle of 30 and the line 13 is parallel with one edge of the end face, leaving a land 15 at said edge. The other end of the recess is defined by an inclined end face 16.

When the tip shown is used for taking a fairly deep cut on a small diameter workpiece, the recess 10 provides sufficient clearance for the chip taken to curl around and form a continuous helical configuration. This ensures that the chip is carried away from the work and does not foul any steady rollers bearing on the work. The tip has eight identical cutting corners.

In the example shown in FIG. 3 the tip is of equilateral triangular cross-section and three recesses 10 are formed in each triangular end face, six identical cutting corners being provided.

The tip shown in FIG. 4 is of rhombic cross-section. The recesses 110 in each end face have the same basic geometry as the recesses 10.

I claim:

1. A throw away tip for a metal cutting tool comprising a right prism of a hard material, each end face of the prism having at least two identical cutting comers and being formed with a plurality of tapering recesses of V-shaped section, each such recess having its narrow end adjacent one of said cutting comers of the associ ated end face and being spaced from the edge of such face so as to define a land extending completely around each end face.

2. A throw-away tip as claimed in claim 1 in which each recess has a pair of flank surfaces inclined to one another at an angle in the range to and equally inclined to the end face.

3. A throw-away tip as claimed in claim 2 in which said flank surfaces intersect the end face on two lines inclined to one another at an angle of 30, one line being parallel to an edge of the end face, whereby a constant width land is provided.

4. A throw-away tip as claimed in claim 3 which the prism is of square cross section and has eight identical cutting comers.

5. A throw-away tip as claimed in claim 3 in which the prism is of equilateral triangular cross-section and has six identical cutting comers.

6. A throw'away tip as claimed in claim 3 in which. the prism is of rhombic cross-section and has four identical cutting comers.

7. A throw-away tip as claimed in claim 3 in which each recess is bounded at the end opposite the associated cutting comer by an inclined end face. 

1. A throw away tip for a metal cutting tool comprising a right prism of a hard material, each end face of the prism having at least two identical cutting corners and being formed with a plurality of tapering recesses of V-shaped section, each such recess having its narrow end adjacent one of said cutting corners of the associated end face and being spaced from the edge of such face so as to define a land extending completely around each end face.
 2. A throw-away tip as claimed in claim 1 in which each recess has a pair of flank surfaces inclined to one another at an angle in the range 105* to 110* and equally inclined to the end face.
 3. A throw-away tip as claimed in claim 2 in which said flank surfaces intersect the end face on two lines inclined to one another at an angle of 30*, one line being parallel to an edge of the end face, whereby a constant width land is provided.
 4. A throw-away tiP as claimed in claim 3 which the prism is of square cross section and has eight identical cutting corners.
 5. A throw-away tip as claimed in claim 3 in which the prism is of equilateral triangular cross-section and has six identical cutting corners.
 6. A throw-away tip as claimed in claim 3 in which the prism is of rhombic cross-section and has four identical cutting corners.
 7. A throw-away tip as claimed in claim 3 in which each recess is bounded at the end opposite the associated cutting corner by an inclined end face. 